FORMATION OF RISK GROUPS FOR TUBERCULOSIS DISEASE IN VARIOUS IMMUNOLOGICAL METHODS OF THE EXAMINATION OF CHILDREN POPULATION

Abstract

When performing mass tuberculin diagnostics in Moscow with coverage of more than 97% of children, the authors evaluated the effectiveness of the formation of risk groups for tuberculosis in children and adolescents with the use of immunological methods such as Mantoux test with 2 TE PPD-L and a test with an tuberculosis recombinant allergen (TRA). There was formed a risk group of cases with altered tuberculin sensitivity (group VI) in which all children underwent a skin test with ATP (Diaskintest preparation) at a dose of 0.2 μg in 0.1 ml. and in the presence of a positive reaction to this test, computed tomography was performed. The low specificity of tuberculin diagnostics in conditions of mass vaccination of children with BCG was found to lead to the fact that the frequency of positive reactions to the Mantoux test is determined primarily by postvaccinal allergy. Accumulation of cases of primary infection, hyperergia and increased reaction is less than 1% per year, and the frequency of positive reactions in the population is above 75%. It was also revealed that only 8.7-11.2% of children and adolescents with a positive reaction to the Mantoux test are examined in an anti-TB dispensary and less than 1% - are to be accounted by phthisiatricians at the risk group. In risk groups selected by the Mantoux sample, in cases with a high threshold of positive response to this test (17 mm and more), the frequency of positive responses to the TRA test is 53.3% in children and 81.4% in adolescents. With age, the proportion of primary infection among all tuberculin-positive Mantoux tests declines from 0.67% in children to 0.06% in adolescents, and the age-related positive responses for the RTA test in risk groups increase from 16.3 to 52.6% respectively. The implementation of the preventive therapy only for children with a high risk of the development of the disease (with a positive RTA test) increases the effectiveness of this therapy and excludes its unreasonable realization.